Müllerianosis of the ureter: a metaplastic lesion.

A 39-year-old nulliparous woman with no history of pelvic surgery or endometriosis was admitted to the hospital in 1988 with acute right ureteral colic without expulsion of calculi, which she had intermittently experienced in the previous 2 years. Excretory urography (IVP) demonstrated a moderately dilated right ureter due to stenosis in the pelvic region (fig. 1, A). Ureteroscopy revealed a stricture, which was dilated with a balloon catheter, followed by clinical improvement. The patient declined surgery. For 10 years she had similar isolated episodes of pain every 2 to 3 months, which were seemingly unrelated to menses. In December 1998 the patient was rehospitalized with incapacitating colic. IVP revealed grade III ureteral hydronephrosis due to a 5 cm. stenotic ureteral segment (fig. 1, B). Ureteroscopy revealed a luminal polypoid bosselated lesion suggestive of endometriosis. However, CA 125 levels were only 7.5 units per ml. A segmental ureteral resection followed by ureterovesical implantation on a “psoic” bladder with an antireflux submucous path was performed. Macroscopically, the 5.3 3 1.5 cm. segment revealed a diffuse thickening of the ureteral wall punctuated by microcysts. Histologically, masses of fibroblastic tissue suboccluded the ureteral lumen involving the lamina propria and inner fibers of the muscularis, and were lined by urothelium which was continuous with a columnar mucinous epithelium. This proliferation was populated by numerous, often cystic, foci of endometrioid, tubal and endocervical epithelia, which had characteristic mullerian immunohistochemical profiles positive for estrogen and progesterone receptors as well as OC125 monoclonal antibody, carbohydrate antigen 19.9, coexpression of vimentin and low molecular weight CAM 5.2 cytokeratins (fig. 2).